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1.
Pharmacol Res ; 189: 106683, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36736415

RESUMO

In spite of the huge advancements in both diagnosis and interventions, hormone refractory prostate cancer (HRPC) remains a major hurdle in prostate cancer (PCa). Metabolic reprogramming plays a key role in PCa oncogenesis and resistance. However, the dynamics between metabolism and oncogenesis are not fully understood. Here, we demonstrate that two multi-target natural products, cannabidiol (CBD) and cannabigerol (CBG), suppress HRPC development in the TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) model by reprogramming metabolic and oncogenic signaling. Mechanistically, CBD increases glycolytic capacity and inhibits oxidative phosphorylation in enzalutamide-resistant HRPC cells. This action of CBD originates from its effect on metabolic plasticity via modulation of VDAC1 and hexokinase II (HKII) coupling on the outer mitochondrial membrane, which leads to strong shifts of mitochondrial functions and oncogenic signaling pathways. The effect of CBG on enzalutamide-resistant HRPC cells was less pronounced than CBD and only partially attributable to its action on mitochondria. However, when optimally combined, these two cannabinoids exhibited strong anti-tumor effects in TRAMP mice, even when these had become refractory to enzalutamide, thus pointing to their therapeutical potential against PCa.


Assuntos
Canabidiol , Neoplasias da Próstata , Humanos , Masculino , Camundongos , Animais , Canabidiol/farmacologia , Morte Celular , Mitocôndrias/metabolismo , Neoplasias da Próstata/metabolismo , Fosforilação Oxidativa , Carcinogênese/metabolismo , Hormônios/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo
2.
Math Biosci ; 355: 108940, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36400316

RESUMO

Using a hybrid cellular automaton with stochastic elements, we investigate the effectiveness of multiple drug therapies on prostate cancer (PCa) growth. The ability of Androgen Deprivation Therapy to reduce PCa growth represents a milestone in prostate cancer treatment, nonetheless most patients eventually become refractory and develop castration-resistant prostate cancer. In recent years, a "second generation" drug called enzalutamide has been used to treat advanced PCa, or patients already exposed to chemotherapy that stopped responding to it. However, tumour resistance to enzalutamide is not well understood, and in this context, preclinical models and in silico experiments (numerical simulations) are key to understanding the mechanisms of resistance and to assessing therapeutic settings that may delay or prevent the onset of resistance. In our mathematical system, we incorporate cell phenotype switching to model the development of increased drug resistance, and consider the effect of the micro-environment dynamics on necrosis and apoptosis of the tumour cells. The therapeutic strategies that we explore include using a single drug (enzalutamide), and drug combinations (enzalutamide and everolimus or cabazitaxel) with different treatment schedules. Our results highlight the effectiveness of alternating therapies, especially alternating enzalutamide and cabazitaxel over a year, and a comparison is made with data taken from TRAMP mice to verify our findings.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Camundongos , Animais , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/genética , Receptores Androgênicos/uso terapêutico , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Microambiente Tumoral
3.
Cancer Lett ; 526: 217-224, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34861311

RESUMO

Prostate cancer (PCa) is a leading cause of cancer mortality in the male population commonly treated with androgen deprivation therapy (ADT) and relapsing as aggressive and androgen-independent castration-resistant prostate cancer (CRPC). In PCa the FGF/FGFR family of growth factors and receptors represents a relevant mediator of cancer growth, tumor-stroma interaction, and a driver of resistance and relapse to ADT. In the present work, we validate the therapeutic efficacy the FDA-approved FGFR inhibitor pemigatinib, in an integrated platform consisting of human and murine PCa cells, and the transgenic multistage TRAMP model of PCa that recapitulates both androgen-dependent and CRPC settings. Our results show for the first time that pemigatinib causes intracellular stress and cell death in PCa cells and prevents tumor growth in vivo and in the multistage model. In addition, the combination of pemigatinib with enzalutamide resulted in long-lasting tumor inhibition and prevention of CRPC relapse in TRAMP mice. These data are confirmed by the implementation of a stochastic mathematical model and in silico simulation. Pemigatinib represents a promising FDA-approved FGFR inhibitor for the treatment of PCa and CRPC alone and in combination with enzalutamide.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Morfolinas/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Antagonistas de Androgênios/farmacologia , Animais , Humanos , Masculino , Camundongos , Morfolinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia
4.
Math Biosci Eng ; 18(6): 8577-8602, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34814314

RESUMO

Prostate cancer is the fifth most common cause of death from cancer, and the second most common diagnosed cancer in men. In the last few years many mathematical models have been proposed to describe the dynamics of prostate cancer under treatment. So far one of the major challenges has been the development of mathematical models that would represent in vivo conditions and therefore be suitable for clinical applications, while being mathematically treatable. In this paper, we take a step in this direction, by proposing a nonlinear distributed-delay dynamical system that explores neuroendocrine transdifferentiation in human prostate cancer in vivo. Sufficient conditions for the existence and the stability of a tumour-present equilibrium are given, and the occurrence of a Hopf bifurcation is proven for a uniform delay distribution. Numerical simulations are provided to explore differences in behaviour for uniform and exponential delay distributions. The results suggest that the choice of the delay distribution is key in defining the dynamics of the system and in determining the conditions for the onset of oscillations following a switch in the stability of the tumour-present equilibrium.


Assuntos
Modelos Biológicos , Modelos Teóricos , Humanos , Fatores de Tempo
5.
J Biosoc Sci ; 53(4): 577-589, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32799940

RESUMO

Tuberculosis (TB) is a globally widespread disease, with approximately a quarter of the world's population currently infected (WHO, 2018). Some risk factors, such as HIV status, nutrition and body mass index, have already been thoroughly investigated. However, little attention has been given to behavioural and/or psychological risk factors such as stress and education level. This study investigated the risk factors for TB diagnosis by statistical analyses of publicly available data from the most recent wave of the Indonesian Family Life survey (IFLS-5) conducted in 2015. Out of 34,249 respondents there were 328 who reported having TB. For comparison and completeness, variables were divided into levels: individual-, household- and community-level variables. The most prominent and interesting variables found to influence TB diagnosis status (on each level) were investigated, and a logistic regression was subsequently developed to understand the extent to which each risk factor acts as a predictor for being diagnosed with TB. Age, health benefit or insurance, stress at work and living in a rural area all showed significant association with TB diagnosis status. This study's findings suggest that suitable control measures, such as schemes for improving mental health/stress reduction and improved access to health care in rural areas should be implemented in Indonesia to address each of the key factors identified.


Assuntos
Características da Família , Tuberculose , Escolaridade , Humanos , Indonésia/epidemiologia , Fatores de Risco , Tuberculose/diagnóstico , Tuberculose/epidemiologia
6.
Cancer Res ; 80(7): 1564-1577, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32029552

RESUMO

Enzalutamide (MDV3100) is a potent second-generation androgen receptor antagonist approved for the treatment of castration-resistant prostate cancer (CRPC) in chemotherapy-naïve as well as in patients previously exposed to chemotherapy. However, resistance to enzalutamide and enzalutamide withdrawal syndrome have been reported. Thus, reliable and integrated preclinical models are required to elucidate the mechanisms of resistance and to assess therapeutic settings that may delay or prevent the onset of resistance. In this study, the prostate cancer multistage murine model TRAMP and TRAMP-derived cells have been used to extensively characterize in vitro and in vivo the response and resistance to enzalutamide. The therapeutic profile as well as the resistance onset were characterized and a multiscale stochastic mathematical model was proposed to link the in vitro and in vivo evolution of prostate cancer. The model showed that all therapeutic strategies that use enzalutamide result in the onset of resistance. The model also showed that combination therapies can delay the onset of resistance to enzalutamide, and in the best scenario, can eliminate the disease. These results set the basis for the exploitation of this "TRAMP-based platform" to test novel therapeutic approaches and build further mathematical models of combination therapies to treat prostate cancer and CRPC.Significance: Merging mathematical modeling with experimental data, this study presents the "TRAMP-based platform" as a novel experimental tool to study the in vitro and in vivo evolution of prostate cancer resistance to enzalutamide.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feniltioidantoína/análogos & derivados , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Antagonistas de Receptores de Andrógenos/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzamidas , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Progressão da Doença , Humanos , Masculino , Camundongos , Nitrilas , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Taxoides/farmacologia , Taxoides/uso terapêutico
7.
Cancers (Basel) ; 11(9)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480336

RESUMO

Bladder tumors are a diffuse type of cancer. Long pentraxin-3 (PTX3) is a component of the innate immunity with pleiotropic functions in the regulation of immune response, tissue remodeling, and cancer progression. PTX3 may act as an oncosuppressor in different contexts, functioning as an antagonist of the fibroblast growth factor/fibroblast growth factor receptor (FGF/FGFR) system, rewiring the immune microenvironment, or acting through mechanisms not yet fully clarified. In this study we used biopsies and data mining to assess that PTX3 is differentially expressed during the different stages of bladder cancer (BC) progression. BC cell lines, representative of different tumor grades, and transgenic/carcinogen-induced models were used to demonstrate in vitro and in vivo that PTX3 production by tumor cells decreases along the progression from low-grade to high-grade advanced muscle invasive forms (MIBC). In vitro and in vivo data revealed for the first time that PTX3 modulation and the consequent impairment of FGF/FGR systems in BC cells have a significant impact on different biological features of BC growth, including cell proliferation, motility, metabolism, stemness, and drug resistance. PTX3 exerts an oncosuppressive effect on BC progression and may represent a potential functional biomarker in BC evolution. Moreover, FGF/FGFR blockade has an impact on drug resistance and stemness features in BC.

8.
Ann Bot ; 124(4): 531-542, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30759181

RESUMO

BACKGROUND AND AIMS: Bioenergy is central for the future energy mix to mitigate climate change impacts; however, its intricate link with the water cycle calls for an evaluation of the carbon-water nexus in biomass production. The great challenge is to optimize trade-offs between carbon harvest and water use by choosing cultivars that combine low water use with high productivity. METHODS: Regional scenarios were simulated over a range of willow genotype × environment interactions for the major UK soil × climate variations with the process-based model LUCASS. Soil available water capacity (SAWC) ranged from 51 to 251 mm and weather represented the north-west (wet, cool), north-east (dry, cool), south-west (wet, warm) and south-east (dry, warm) of the UK. Scenario simulations were evaluated for small/open narrow-leaf (NL) versus large/closed broad-leaf (BL) willow canopy phenotypes using baseline (1965-89) and warmer recent (1990-2014) weather data. KEY RESULTS: The low productivity under baseline climate in the north could be compensated by choosing BL cultivars (e.g. 'Endurance'). Recent warmer climate increased average productivity by 0.5-2.5 t ha-1, especially in the north. The modern NL cultivar 'Resolution' had the smallest and most efficient water use. On marginal soils (SAWC <100 mm), yields remained below an economic threshold of 9 t ha-1 more frequently under baseline than recent climate. In the drought-prone south-east, 'Endurance' yielded less than 'Resolution', which consumed on average 17 mm year-1 less water. Assuming a planting area of 10 000 ha, in droughty years between 1.3 and 4.5 × 106 m3 of water could be saved, with a small yield penalty, for 'Resolution'. CONCLUSIONS: With an increase in air temperature and occasional water scarcities expected with climate change, high-yielding NL cultivars should be the preferred choice for sustainable use of marginal lands and reduced competition with agricultural food crops.


Assuntos
Salix , Agricultura , Mudança Climática , Fenótipo , Água
9.
Cancer Res ; 75(15): 2975-86, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26069250

RESUMO

Prostate cancer is highly sensitive to hormone therapy because androgens are essential for prostate cancer cell growth. However, with the nearly invariable progression of this disease to androgen independence, endocrine therapy ultimately fails to control prostate cancer in most patients. Androgen-independent acquisition may involve neuroendocrine transdifferentiation, but there is little knowledge about this process, which is presently controversial. In this study, we investigated this question in a novel model of human androgen-dependent LNCaP cells cultured for long periods in hormone-deprived conditions. Strikingly, characterization of the neuroendocrine phenotype by transcriptomic, metabolomic, and other statistically integrated analyses showed how hormone-deprived LNCaP cells could transdifferentiate to a nonmalignantneuroendocrine phenotype. Notably, conditioned media from neuroendocrine-like cells affected LNCaP cell proliferation. Predictive in silico models illustrated how after an initial period, when LNCaP cell survival was compromised by an arising population of neuroendocrine-like cells, a sudden trend reversal occurred in which the neuroendocrine-like cells functioned to sustain the remaining androgen-dependent LNCaP cells. Our findings provide direct biologic and molecular support for the concept that neuroendocrine transdifferentiation in prostate cancer cell populations influences the progression to androgen independence.


Assuntos
Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Algoritmos , Androgênios/metabolismo , Transdiferenciação Celular/efeitos dos fármacos , Análise por Conglomerados , Meios de Cultivo Condicionados/farmacologia , Regulação Neoplásica da Expressão Gênica , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Modelos Teóricos , Fenótipo , Reação em Cadeia da Polimerase , Neoplasias da Próstata/genética , Células Tumorais Cultivadas
10.
Math Biosci Eng ; 12(3): 473-90, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25811557

RESUMO

Botanical epidemic models are very important tools to study invasion, persistence and control of diseases. It is well known that limitations arise from considering constant infection rates. We replace this hypothesis in the framework of delay differential equations by proposing a delayed epidemic model for plant--pathogen interactions with host demography. Sufficient conditions for the global stability of the pathogen-free equilibrium and the permanence of the system are among the results obtained through qualitative analysis. We also show that the delay can cause stability switches of the coexistence equilibrium. In the undelayed case, we prove that the onset of oscillations may occur through Hopf bifurcation.


Assuntos
Modelos Biológicos , Doenças das Plantas/parasitologia , Doenças das Plantas/estatística & dados numéricos , Fenômenos Fisiológicos Vegetais , Plantas/parasitologia , Dinâmica Populacional , Simulação por Computador , Fatores de Tempo
11.
J Sci Food Agric ; 91(10): 1733-6, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21656775

RESUMO

Biofuels produced from willow could help reduce our dependence on fossil fuels. To maximise yields per hectare light interception and utilisation of the plant canopy need to be optimised. Jennifer Cunniff and Marianna Cerasuolo explain how this target can be reached by integrating morphological field measurements and modelling techniques.


Assuntos
Biocombustíveis , Biomassa , Luz , Salix/fisiologia , Coleta de Dados , Modelos Biológicos
12.
J Chem Ecol ; 36(3): 339-49, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20186470

RESUMO

The role of extracellular fatty acids in the interference between two algae, Chlorella vulgaris Beijerink and Pseudokirchneriella subcapitata (Korshikov) Hindak, was assessed by the co-cultivation of the two selected strains, as well as by the chemical analysis of exudates from the culture media of single strain cultures. The effect of culture age and phosphate limitation was evaluated. The experiments showed that the composition and amount of fatty acids, released by C. vulgaris and by P. subcapitata, both in a batch and in a continuous monoculture, depend on the culture age and on the phosphate concentration in the culture medium. We also found that the amount of chlorellin generated in the two algae co-culture increased and was almost exclusively constituted by a mixture of C18 fatty acids. By using the evaluated concentrations of these fatty acids, an artificial chlorellin was prepared. The toxicity of this mixture to P. subcapitata appears to be similar to that of the natural chlorellin. For both algae, a stimulation of growth was observed at low concentrations of the natural chlorellin, whereas higher concentrations produced inhibitory effects on both species. However, P. subcapitata was much more sensitive than C. vulgaris. By using some of these new experimental results, two new mathematical models have been used to describe the toxicity of chlorellin to C. vulgaris and to the interference between C. vulgaris and P. subcapitata, respectively.


Assuntos
Chlorella vulgaris/química , Clorófitas/efeitos dos fármacos , Ácidos Graxos/toxicidade , Modelos Biológicos , Clorófitas/crescimento & desenvolvimento , Técnicas de Cocultura , Ácidos Graxos/isolamento & purificação
13.
Math Biosci Eng ; 3(1): 37-50, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20361806

RESUMO

The dynamics of a differential functional equation system representing an allelopathic competition is analyzed. The delayed allelochemical production process is represented by means of a distributed delay term in a linear quorum-sensing model. Sufficient conditions for local asymptotic stability properties of biologically meaningful steady-state solutions are given in terms of the parameters of the system. A global asymptotic stability result is also proved by constructing a suitable Lyapunov functional. Some simulations confirm the analytical results.

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